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Sure, you can simply loop through your eMail addresses and send the mails, BUT you may run in to memory limits, or bulk eMail limits depending on your server configuration, and how many mails you are trying to send.
Long answer:
Probably the best way to do this is to create a PHP script that runs as a chron job. Use a database and when you need to send a bulk eMail, write the entries to the database, each one with the information required for the mail. Every so often, have your automated script run, and batch the next several mails in the DB. Mail won't go out instantly, but if your chron runs every 2 minutes, say, and mails 20 emails in a go, it would take about 10 minutes to send about 100 mails. You could handle 600 in an hour, which is not too shabby, and it would greatly decrease your servers load.